الفهرس 
Pathological Studies on Plant Parasitic Nematodes Attacking some Vegetable CropsOnly 14 pages are availabe for public view
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Abstract
Survey study was conducted to determine the plant parasitic nematodes associated with spinach, Swiss chard and table beet plants. A total of 854 root and soil samples were collected from the rhizosphere of spinach, Swiss chard and table beet plants. The surveyed
governorates and their respective numbers of soil samples were as follows: Alexandria 230, El-Behera 206, El-Gharbia 138, El-Monufia 211 and Kafr El-Sheikh 69 samples. A total of 14 and 15 nematode genera were detected in soil samples of El-Monufia and ElBehera governorates. Soil samples of El-Gharbia and Kafr El-Sheikh showed 10 and 12
nematode genera while soil samples of Alexandria governorate had 11 nematode genera the root-knot nematode Meloidogyne was very common and followed with the genera Helicotylenchus, Heterodera, Pratylenchus and Tylenchorhynchus. The genera
Criconema, Criconemella and Tylenchus were quite common while the other genera
(Ditylenchus, Hoplolaimus, Psilenchus, Rotylenchulus, Rotylenchus, Trichodorus, and Xiphinema) were less common. The morphological study show that only three species of the root-knot nematodes namely M. arenaria, M. incognita and M. javanica were identified in the collected galled root samples from spinach, Swiss chard, and table beet
plants. M. incognita was very common in northern Egypt with frequency of occurrence (FO) of 56.7 – 72.7%, followed by M. javanica with FO of 20 – 34%, whereas M. arenaria had the lowest FO of 7.3 – 9.3%.
2. Five spinach cultivars (Barkly, Orient, Passiphic, Salonicy and Balady), two Swiss chard cultivars (Ford Hook and Balady) and four table beet cultivars (Asgro Wonder, Detroit Spainal, Detroit Dark Red and Balady) were determined for their reactions to Heterodera
schachtii under greenhouse conditions. The results showed that the tested spinach cultivar Balady was susceptible to H. schachtii while cvs Orient, Salonicy, Barkly and Pacific
were moderately susceptible. Swiss chard cv. Balady was susceptible to H. schachtii but Ford Hook cultivar was moderately susceptible. Meanwhile, table beet cvs Balady, Detroit
Dark Red and Detroit Spainal were susceptible to H. schachtii but cv. Asgro Wonder was moderately susceptible. Shoot and root dry weights of the tested crops were significantly reduced with H. schachtii infection.
3. Five spinach cultivars (Barkly, Orient, Passiphic, Salonicy and Balady), two Swiss chard cultivars (Ford Hook and Balady) and four table beet cultivars (Asgro Wonder, Detroit Spainal, Detroit Dark Red and Balady) were determined for their reactions to Heterodera
trifolii under greenhouse conditions. Spinach cultivar Balady was susceptible to H. trifolii.
Orient, Salonicy and Barkly cultivars were moderately susceptible to H. trifolii while cv.
Pacific was resistance to H. trifolii. Infections with H. trifolii reduced the shoot and root dry weights of cvs Balady and Orient. Swiss chard cv. Balady was moderately susceptible to H. trifolii while cv. Ford Hook was resistance. Nematode infection no cause significant
changes in shoot and root dry weights of the Swiss chard tested cultivars. On the other hand, table beet cvs Balady, Detroit Dark Red and Detroit Spainal cultivars were moderately susceptible to H. trifolii. Asgro Wonder cultivar was resistance to H. trifolii.
95 Moreover, infections with H. trifolii caused significant reduce in shoot and root dry weights of table beet cvs Balady and Detroit Dark Red.
4. The reactions of five spinach cultivars (Barkly, Orient, Passiphic, Salonicy and Balady),
two Swiss chard cultivars (Ford Hook and Balady) and four table beet cultivars (Asgro Wonder, Detroit Spainal, Detroit Dark Red and Balady) to Meloidogyne incognita and M.
javanica were determined. Spinach Salonicy cultivar was susceptible to Meloidogynespecies. On the other hand, Pacific cultivar was moderately susceptible to M. javanica but
was susceptible to M. incognita. Swiss chard cv. Ford Hook was susceptible to M.
arenaria and M. javanica but, it was highly susceptible to M. incognita. Table beet Detroit
Dark Red cv. was susceptible to M. arenaria but it was highly susceptible to M. javanica and M. incognita. Also, results indicated that Detroit Spainal cv. was susceptible to the
tested Melidogyne species. On the other hand, table beet cv. Asgro Wonder was
moderately susceptible to M.arenaria but it was susceptible to M. javanica and M.
incognita. Results revealed that Infections with Meloidogyne species caused reduce in shoot and root dry weights of three tested crops.